Is Your Floss Toxic? How to Find and Use Safe Dental Floss

Flossing is too important to skip—and safe dental floss can make you feel even better about your habit. In this article, discover what toxic ingredient may be hiding in your floss, which floss is bad for the planet, and what to try instead.

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Hi, I’m Dr. B, practicing functional dentist for 35 years. I graduated from the Dugoni School of Dentistry in San Francisco, CA in 1987 and am a member of the American Academy of Dental Sleep Medicine (AADSM), Academy of General Dentistry (Chicago, IL), American Academy for Oral Systemic Health (AAOSH), and Dental Board of California. I'm on a mission to empower people everywhere with the same evidence-based, easy-to-understand dental health advice that my patients get. Learn more about Dr. B

It might be a question you’ve never considered, but are you using safe dental floss?

Flossing your teeth is a key component to excellent dental health. But you may be surprised to know what some manufacturers use to make this important dental necessity more marketable.

Is dental floss toxic? Some types of floss are made with toxic chemicals like Teflon. I’m also concerned about the impact of nylon on the environment, though I don’t see it as a toxin in the same way as Teflon.

I want to tell you about the ways toxic floss is made and provide a few alternatives for safe dental floss for your entire family.

Let’s take a look.

Ask the Dentist is supported by readers. If you use one of the links below and buy something, Ask the Dentist makes a little bit of money at no additional cost to you. I rigorously research, test, and use thousands of products every year, but recommend only a small fraction of these. I only promote products that I truly feel will be valuable to you in improving your oral health.

Toxic Ingredients in Dental Floss


Yes, you are reading that word right: Teflon.

One of the ingredients used to make waxed floss is the same chemical group as the coating on many brands of non-stick pans.

Granted, you aren’t likely to swallow floss or ingest large amounts of Polytetrafluoroethylene (PTFE). But PTFE and PFOA (a related chemical) have been linked to adverse health conditions such as thyroid disease.

This is important because the most dangerous ways you may be exposed to Teflon are food and floss. Even tiny particles making it into your system are likely to cause serious issues.

Teflon exposure has been linked to:

Hormone imbalance
Cancer (1)
Autoimmune disease (2)
Neurotoxicity and Alzheimer’s disease (3, 4)

Before you feel overwhelmed by this information, let me encourage you: there are some quality alternatives to the popular brands we are used to seeing. I will recommend some of my favorites later in this post.

One of my personal favorites used to be Glide Pro-Health floss by Oral B. Once I discovered it was coated with Teflon, though, I quickly began looking for a healthier option.

See my top options in the “Safe Dental Floss to Try” section below.


Not only are nylon and polyester flosses made from petroleum, the wax on most conventional floss is also petroleum-derived.

The Environmental Working Group (EWG) gives petrolatum, or petroleum, a rating of 4/10 when used in personal care items.

I should start by saying that there isn’t much research at all when it comes to petroleum in floss.

What I can tell you is that topical petroleum seems to carry some risks.

The EWG estimates that 22% of personal care products that contain petroleum-based substances are contaminated with 1,4-dioxane and up to two dozen other toxins. (51,4-dioxane is carcinogenic to animals when inhaled regularly. (6)

Using petroleum products with infants resulted in an increased chance for candidiasis, according to one study. (7) This is especially important because candidiasis of the mouth, called oral thrush, is a common problem for children.

Finally, petroleum products may behave as endocrine disruptors. (8) These are natural or synthetic chemicals that act like hormones your body produces.

We’re all exposed to at least a low level of endocrine disruptors throughout our lives, but there are people more sensitive to these chemicals than others.

Now, you might be reading this in horror, thinking, “Oh no! I should stop flossing forever!”

If that’s the case, let me take a moment to reassure you: There is no established link between using floss and cancer, oral thrush, or hormonal conditions. When you floss, your body is exposed to very little of the compounds found in petroleum.

The key here is that if you can avoid even the smallest amount of these chemicals…why not?

To give you a little perspective…If a patient asked me what was better, to floss with petroleum-coated floss, or to stop flossing, I would say keep flossing with the same stuff.

Why? Because there is a direct link between not flossing and more oral disease. Since what happens in the mouth happens in the body, failing to floss can open the door to a host of problems.

If you’re interested in safer floss options that don’t use petroleum, keep reading.

dental floss

Nylon + polyester

Most floss is made from nylon, while some brands have started using polyester. Both of these are petroleum-based products. defines nylon as: “A tough, lightweight, elastic synthetic polymer with a protein-like chemical structure, able to be produced as filaments, sheets, or molded objects.”

Little pieces of nylon and petroleum can break off from your floss. The question is: where does it go? Do you swallow it?

It’s not something the body can break down any more than nylon products can break down in a garbage dump.

I don’t want that in my body—it reminds me of those toxic, plastic rings they find in the ocean. Where is it going? We aren’t sure. And we don’t know what’s happening to it later on.

While where it goes in my body is important, I’m even more concerned about the way nylon and polyester impact the environment.

Neither of these materials are biodegradable. We have no way of knowing the impact they have in dumps and landfills.

Plus, the production of nylon creates chemicals that can pollute both the air and water. (9)

However, if it’s between nylon/polyester or Teflon…I recommend nylon every time. In fact, some of the flosses I recommend contain nylon.

I want to be clear here: nylon is likely not toxic in the same way Teflon is toxic to your body. I’m more uncomfortable with a) what we don’t know about nylon yet and b) the way its production hurts the environment.


Although it might not be something you watch out for in floss, some brands use synthetic fragrance chemicals to flavor their floss. In fact, I used to promote the largest brand guilty of it!

Synthetic fragrance chemicals are often derived from petroleum and have been linked to major health problems like cancer, brain disease, allergies, and even birth defects. They’re frequently comprised of phthalates, which disrupt hormones and are generally substances to avoid throughout your life.

Many other countries have banned the majority of these chemicals, but the US has over 3,000 “approved” fragrance chemicals. Companies don’t have to disclose what fragrance chemicals are used in their products; they simply add the word “fragrance” to ingredient labels.

If you’re using a flavored floss, check to ensure it’s flavored with a natural substance and not synthetic fragrance.

Do I really need to floss?

This is easiest question I’ve ever answered! YES, flossing is absolutely essential to good oral and dental health.

Many people have argued that, although they don’t floss, they regularly brush. They have a pain-free mouth, and never see food between their teeth.

While that may seem proof-positive that flossing isn’t necessary, seeing isn’t always believing. Bacteria can be microscopic and invisible to the eye. Even if your teeth are not tightly spaced, food particles can be trapped, creating a home in which plaque and tartar happily reside.

And while it may not cause physical pain, it will seriously affect your teeth over time. In addition to that, what’s in your mouth is swallowed into your body. This bacteria has been the cause of serious health issues.

In the article, Why Shouldn’t We Ignore the Oral Microbiome, I address the vital connection between the oral and intestinal microbiome.

Most dentists overlook the importance of this connection. But it’s simply too important to overlook, and forming proper, simple dental habits are the first key to achieving overall body health.

So, which is more important: brushing or flossing? Actually, I’d say it’s flossing!

I know that’s surprising for many people to hear. But, especially if you follow a mostly Paleo or keto type diet with limited starchy carbs, brushing is probably not as vital as you think.

Don’t get me wrong, though. I’m definitely not advocating you stop brushing your teeth.

Safe Dental Floss to Try

Is there a best safe dental floss? Here are some best dental floss options I’ve found.

100% Sustainable & 100% Non-Toxic
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Dental Lace Refillable Floss

This company’s floss is one of my favorite options for floss out there because they provide a reusable glass container (no plastic!) and use silk, which is totally biodegradable. Their packaging is also recyclable AND biodegradable. Just be aware that Dental Lace (and all silk floss) has a tendency to break more easily than nylon—which I think is an acceptable trade for increased environmental friendliness.

Buy Now

Mostly Sustainable & 100% Non-Toxic
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Radius Natural Silk Floss

Because I prefer unwaxed floss in my own daily routine, this is my number one pick. The floss itself is 100% biodegradable since it’s made from silk rather than nylon—plus, the plastic container can be recycled. Since it’s silk, it may break more often than other flosses.

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Less Toxic
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Boka Mint Floss

Teflon-free, this nylon floss is waxed with natural beeswax. It comes in a pleasant mint flavor and is relatively inexpensive ($4-$5 for 30 yards). Good for your teeth, good for your checkbook.

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Universal Floss Handle
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GUM Flossmate Handle

Not a big fan of wrapping floss around your fingers? This reusable floss handle is a convenient companion to any floss you choose—plus, you don’t have to throw out a disposable floss pick.

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For people who hate normal floss
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Waterpik Countertop

This one is the most expensive of the 3 products I’m sharing in this article. But, it is definitely the most effective product. At around $64, if you can swing it, you won’t be disappointed with the result. Plus, it uses no traditional floss whatsoever, which means you get safe dental floss with no health or environmental drawbacks.

Buy Now

Frequently Asked Questions about Safe Dental Floss

Q: Should I use waxed or unwaxed dental floss?

A: At the end of the day, the straight answer is, it doesn’t matter. What does matter is that consistent, frequent flossing takes place.

Some pros of waxed floss:

  • Most comfortable (for many users)
  • Different flavors enhance the flossing experience
  • Many people experience less bleeding than when using unwaxed

Some pros of unwaxed floss:

  • Thinner than waxed, easier to get between tightly spaced teeth
  • Different flavors irritate some pregnant women, folks with sensitive tummies
  • Price of product is less than waxed, and thus, preferable

To answer the frequently asked question: Which is best—waxed or unwaxed floss?

That’s easy! The best floss, the most safe dental floss for you is the one you use, because flossing is that important.

Q: Is it okay to reuse floss?

A: No. The bacteria, food and other residue removed by flossing will remain on the floss product, no matter how you might try to clean it.

Even my “best floss” recommendations above are not so expensive that you would need to use the same piece a second time, and risk your health in the process.

Q: What are the different types of floss?

A: Most of the time, floss is made of:

  • Teflon
  • Nylon
  • Silk
  • Polyester

It may be “infused” with activated charcoal, but most “charcoal” flosses are still nylon or polyester-based.

Then, waxed floss is coated with a variety of waxes, like:

  • Petroleum
  • Beeswax
  • Coconut oil
  • Synthetic fragrance

You can get floss in large spools or floss picks (with a small bit of floss in an access handle to make it easier to reach back teeth). Water flossers are a great option for people who want to have a more dentist’s office-type of experience with flossing.

Q: What if I hate to floss? What can I do?

A: Flossing is rarely a “fun” habit. However, there are a few ways to make it a little easier.

  1. Try floss sticks. Whether you go for the reusable handle, like the one I mentioned above, or disposable floss sticks, starting a flossing habit should be a top priority. Floss sticks or handles make flossing much easier and won’t hurt your fingers, like wrapping floss might.
  2. Floss one tooth. A habit can be difficult to form, especially if you associate it with pain or discomfort. While you’re getting started, try just one tooth each day to get used to flossing.
  3. Remind yourself it will get better over time. If your gums bleed during flossing, that’s a sign of gingivitis. Unchecked, gingivitis can lead to all sorts of very painful and problematic conditions. If you’re able to power through the discomfort, you’ll find your gums bleed less over time and the mild pain you may encounter goes away. Plus, you’ll save yourself thousands of dollars and years of pain in the future!
  4. Use a water flosser. Water flossers like the Waterpik above are potentially just as effective as standard string floss. (10) Try one of these countertop devices for a pleasant, string-free experience.

Q: What do you think about air/water flossers?

A: Unlike the standard Waterpik-like devices that use strictly water to clean your teeth, air/water flossers blow air and water using a similar tip. I am not a fan of these devices, as they don’t have enough power to be effective.

Let’s recap.

Some common dental floss brands use toxic, harmful chemicals and substances.

The chemicals in Teflon may pass to your bloodstream through the sensitive blood vessels in the mouth. PTFE and PFOA have some incredibly dangerous impacts on human health, so I recommend avoiding Teflon floss altogether. (The most common Teflon floss is Glide Pro-Health floss.)

Many types of floss are coated in petroleum. The science behind petroleum and the human body is somewhat limited, but exposure to a lot of it is associated with some nasty stuff. On the whole, I would recommend you avoid petroleum-waxed floss if you can.

Nylon is not actually a toxic substance like Teflon. However, nylon is not biodegradable (which is concerning to me if it’s able to accumulate in the body). This fact, coupled with the manufacturing process creating harmful chemicals that pollute the air and water, makes it clear that nylon is a poor environmental choice.

Sure, it’s safe to assume most people don’t swallow their floss. But the way floss is supposed to be used makes it impossible to keep these chemicals from coming off the floss and out into your mouth.

Here’s the great news—you’ve got healthy options to choose from!

Maybe you’ll choose beeswax or coconut oil as an alternative to chemical coating of floss. Maybe you will choose unwaxed floss.

But what’s most important is the choice to floss!

If you have any additional questions about flossing, just ask me and I’ll respond personally.

Learn More: Hospitals Are Fighting Pneumonia With Brushing and Flossing (And Winning)

10 References

  1. Environmental Working Group, (2007). EWG assessment of EPA draft human health risk assessment for the teflon chemical PFOA. Retrieved from:
  2. Steenland, K., Zhao, L., Winquist, A., & Parks, C. (2013). Ulcerative colitis and perfluorooctanoic acid (PFOA) in a highly exposed population of community residents and workers in the mid-Ohio valley. Environmental health perspectives, 121(8), 900. Full text:
  3. Shaw, C. A., & Tomljenovic, L. (2013). Aluminum in the central nervous system (CNS): toxicity in humans and animals, vaccine adjuvants, and autoimmunity. Immunologic research, 56(2-3), 304-316. Abstract:
  4. Mirza, A., King, A., Troakes, C., & Exley, C. (2017). Aluminium in brain tissue in familial Alzheimer’s disease. Journal of Trace Elements in Medicine and Biology, 40, 30-36. Full text:
  5. Environmental Working Group (EWG). 2007. EWG Research Shows 22 Percent of All Cosmetics May Be Contaminated With Cancer-Causing Impurity. Retrieved from:
  6. Kasai, T., Kano, H., Umeda, Y., Sasaki, T., Ikawa, N., Nishizawa, T., … & Fukushima, S. (2009). Two-year inhalation study of carcinogenicity and chronic toxicity of 1, 4-dioxane in male rats. Inhalation toxicology21(11), 889-897. Abstract:
  7. Campbell, J. R., Zaccaria, E., & Baker, C. J. (2000). Systemic candidiasis in extremely low birth weight infants receiving topical petrolatum ointment for skin care: a case–control study. Pediatrics105(5), 1041-1045. Abstract:
  8. Vrabie, C. M., Candido, A., van Duursen, M. B., & Jonker, M. T. (2010). Specific in vitro toxicity of crude and refined petroleum products: II. Estrogen (α and β) and androgen receptor‐mediated responses in yeast assays. Environmental toxicology and chemistry29(7), 1529-1536. Abstract:
  9. Chen, H. L., & Burns, L. D. (2006). Environmental analysis of textile products. Clothing and Textiles Research Journal, 24(3), 248-261. Full text:
  10. Lyle, D. M. (2012). Relevance of the water flosser: 50 years of data. Compendium of continuing education in dentistry (Jamesburg, NJ: 1995), 33(4), 278-80. Abstract: